Recent progress in human embryonic stem cell (ESC) and induced pluripotent stem cell (iPSC) research opens up unprecedented opportunities for the development of new strategies to repair and replace organs including liver. It is also highly desirable to establish disease models using patient specific iPS cells derived from the diseased tissues that contain somatic mutations which are not present in other tissues or in healthy individuals. Hepatocarcinogenesis is considered as a multi-step process involving a number of different genetic alterations caused by environmental factors such as alcohol. The accumulated effects ultimately lead to malignant transformation of hepatocytes. The molecular events underlying each step of the process are not fully understood and better model systems are needed to delineate the mechanism. Complimentary to current available models, iPS technology offers unique opportunity to preserve and study cells at various disease stages that lead to hepatocellular carcinoma (HCC). Towards the goal of studying liver diseases using pluripotent stem cells, we have systematically improved reprogramming of human postnatal cells including primary hepatocytes.Importantly, we were able to differentiate iPS cells into early and mature hepatic cells. In this study, we propose to explore the possibility of modeling alcohol related HCC using patient- and disease- specific iPS cells. We plan to generate iPS cell lines from liver tissues of HCC patients with chronic alcohol consumption history. After characterization of these iPS cell lines, we will differentiate them into different stages of hepatic cells, using iPS cells from healthy donors as controls. We will test the hypothesis that the hepatic cells generated from diseased iPS cells possess certain characteristics of the disease (i.e. HCC). In particular, their ability to terminally differentiate, to proliferate and to undergo apoptosis will be determined. We will also initiate transplantation of these iPSC derived hepatic cells into immunodeficient mice to determine the in vivo activity of the cells. Completion of this study will help establish more human HCC relevant, innovative in vitro and in vivo models to systematically study the molecular mechanisms and the contribution of alcohol and other risk factors to different stages of hepatocarcinogenesis. PUBLIC HEALTH RELEVANCE: Completion of this study will help establish more human HCC relevant, innovative in vitro and in vivo models to systematically study the molecular mechanisms and the contribution of alcohol and other risk factors to different stages of hepatocarcinogenesis.